In the flaskless molding method, an attempt has been made to improve work efficiency by using a well-known flaskless molding machine. For example, Japanese Early-Patent Publication No. 04 [denotes the year 1992]-66245 suggests that a well-known flaskless molding machine be combined with a pattern-changing device. The pattern exchanges mechanically and automatically, rather than manually, for a new pattern plate.
However, the publication describes “the arrangement of the main unit 10 of the molding machine is a well-known one that has been used in a so-called flaskless molding method.” Clearly, the flaskless molding machine employed as in the disclosure is a well-known one that has been used in a conventional flaskless molding method, where the pattern plates are exchanged manually. Therefore, the processes of defining a pair of molding spaces as in the flaskless molding machine of this disclosure are the same as those in the conventional flaskless molding method, where the pattern plates are manually exchanged. That is, a pattern plate having patterns on both faces is horizontally clamped between a pair of flasks in a sandwich relationship at the side of the molding machine. They are then rotated in unison to a location below a sand-supplying device such that they are vertical. Then a pair of opposed squeeze heads is horizontally inserted in the pair of the vertical flasks, which between them clamp the pattern plate, to define a pair of molding spaces. Accordingly, in the conventional flaskless molding machine the processes of defining a pair of molding spaces could not begin until the cope and drag flasks that clamp the pattern plate therebetween are in the vertical position. Because this situation results in a molding cycle in the conventional flaskless molding machine that still requires much time, the production efficiency of molds is low.
The resulting molds that are produced from the flaskless molding machine are stacked upper and lower molds. Before stacking them a core is often manually placed in the mold within the drag flask. However, in the conventional flaskless molding machine, the cope flask that is located immediately above the drag flask can interfere with an operator who is trying to place the core in the lower mold within the drag flask. Because the conventional flaskless molding machine provides no ready access to an operator who is trying to place the core in the lower mold, it is also a bad factor in the efficiency of making molds of the flaskless molding machine.